The present invention generally relates to a system and a method for sorting articles. More specifically, the present invention relates to transporting of mail pieces to destinations on more than one vertical level for sorting.
It is, of course, known to deliver mail pieces to a plurality of destinations based on predetermined requirements, such as a particular zip code, for example. However, current operational systems require a significant amount of floor space in order to implement the sorting process. The floor space, commonly referred to as a "foot print", for current systems requires space for the machine itself, space for access to the machine, and space for staging of input and output mail.
One such system is known and generally illustrated in U.S. Pat. No. 4,503,977 to Kohno et el.
The '977 patent requires a significant amount of floor space to implement the sorting of mail to a plurality of stacking bins. The bins are arranged in a row as a result of optically scanning and reading zip codes on the mail. Whenever a predetermined amount of mail is stacked in a stacking bin, the mail is transferred to a conveyance section. When the sorting operation has ended, the mail sorting apparatus detects if any mail exists on the conveyance section. This operation continually repeats until all mail is removed from the stacking bins.
Another system for sorting and processing of mail pieces is shown in U.S. Pat. No. 3,884,370 to Bradshaw et al. The system disclosed in the '370 patent includes mechanical carriers magnetically encoded with sort destinations to transport and remain with respective items through a processing cycle. A monorail conveyor distribution system has a three-dimensional suspension system consisting of belts to provide transport, storage, switching and supporting of carriers during the processing operation.
As is apparent in the '370 and '977 patents, a significant amount of floor space is required for providing mail sorting operations. Further, these prior art mail sorting systems are inefficient in terms of handling of mail pieces as well as time required for conducting a sorting operation.
A need, therefore, exists for an improved system and method for sorting articles, particularly mail pieces.